The startup wallet and exchange will be reimbursing losers from the temporary crash, determined to be caused by a multi-million dollar market sell order which triggered a domino reaction of stop-loss orders on GDAX. Moreover, if you were lucky enough to have been a buyer on the short-lived dip, the trade will be honored!
This is more of a sign of goodwill than an admission of any wrongdoing. GDAX’s exchange performed just the way it was supposed to – and the same way a market like the NYSE would function if a proportionally large market sell order was placed. If anything, this should be a reminder to traders how risky it can be to trade on margin, and that cryptocurrency markets can be just as unforgiving (and sometimes more) as other equity markets.
https://techcrunch.com/2017/06/24/coinbase-is-reimbursing-losses-caused-by-the-ethereum-flash-crash/